Predistortion of a radio frequency power amplifier , Report no. LiTH-ISY-R-2974
نویسنده
چکیده
A linearized digital radio frequency (RF) power amplifier (PA), a switched RF PA, is more power efficient than an analog amplifier, but may cause interference in adjacent transmitting channels similar to analog amplifiers. This interference is due to the inherent nonlinearities, and this project investigated the possibility of reducing this interference by using a prefilter, a predistorter, to improve the linearity of the linearized digital amplifiers. Two models, a forward model and an inverse model, the predistorter, have been estimated from measured data. The model addresses the gain and phase errors of the power amplifier. The first experiments show promising results, like improved Adjacent Channel Leakage Ratio (ACLR) for WCDMA and improved margins to the spectral mask for EDGE 8PSK measured at 2 GHz.
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